This guide shows you three ways to change which Claude model you're using with Claude Code: the quick /model command for instant changes, the --model flag for one-time session changes, and environment variables to set your preferred model as the permanent default.
Easiest Method: Use /model Command
The simplest way to change models is to use the /model command directly within Claude Code. This works immediately without restarting your terminal.
Start Claude Code:
claude.Type
/modeland choose your desired model from the interactive menu.Your model change takes effect immediately.
Note: You can check your current model anytime by running /status in Claude Code.
Supported Models
Opus 4.1,
claude-opus-4-1-20250805Opus 4,
claude-opus-4-20250514Sonnet 4,
claude-sonnet-4-20250514Sonnet 3.7,
claude-3-7-sonnet-20250219Haiku 3.5,
claude-3-5-haiku-20241022
⚠️ Model Access: When using a Pro plan with Claude Code, you will not be able to use Opus models.
Change Model for Current Session Only
Use the --model flag when starting Claude Code.
Start a fresh Terminal session.
Enter the following commands (depending on the model you’d like to use for that session):
For Opus 4.1:
claude --model claude-opus-4-1-20250805For Opus 4:
claude --model claude-opus-4-20250514For Sonnet 4:
claude --model claude-sonnet-4-20250514For 3.7 Sonnet:
claude --model claude-3-7-sonnet-20250219For 3.5 Haiku:
claude --model claude-3-5-haiku-20241022
Note: The Opus models will be unavailable to Pro plan users logged into Claude Code.
Change Default Model for All Future Sessions
Step 1) Check your shell type by running: echo $SHELL
/bin/zsh→ You're using zsh (macOS default)/bin/bash→ You're using bash (Linux default)
Step 2) Add model setting to your shell config:
For ZSH users (macOS):
Opus 4.1:
echo 'export ANTHROPIC_MODEL="claude-opus-4-1-20250805"' >> ~/.zshrcOpus 4:
echo 'export ANTHROPIC_MODEL="claude-opus-4-20250514"' >> ~/.zshrcSonnet 4:
echo 'export ANTHROPIC_MODEL="claude-sonnet-4-20250514"' >> ~/.zshrc3.7 Sonnet:
echo 'export ANTHROPIC_MODEL="claude-3-7-sonnet-20250219"' >> ~/.zshrc3.5 Haiku:
echo 'export ANTHROPIC_MODEL="claude-3-5-haiku-20241022"' >> ~/.zshrc
For BASH users (Linux):
Opus 4.1:
echo 'export ANTHROPIC_MODEL="claude-opus-4-1-20250805"' >> ~/.bashrcOpus 4:
echo 'export ANTHROPIC_MODEL="claude-opus-4-20250514"' >> ~/.bashrcSonnet 4:
echo 'export ANTHROPIC_MODEL="claude-sonnet-4-20250514"' >> ~/.bashrc3.7 Sonnet:
echo 'export ANTHROPIC_MODEL="claude-3-7-sonnet-20250219"' >> ~/.bashrc3.5 Haiku:
echo 'export ANTHROPIC_MODEL="claude-3-5-haiku-20241022"' >> ~/.bashrc
Step 3) Apply the changes:
For ZSH:
source ~/.zshrcFor BASH:
source ~/.bashrc
Step 4) Close Terminal completely, then reopen it.
Step 5) Start Claude Code in a fresh Terminal session: claude.
Now your chosen model will be the default for all future Claude Code sessions.